Method of attaching metal closures to containers



Dec. 7, 1948. J, CQYLE 2,455,737

' IETHOD F.ATTACHING ETAL CLOSURES TO CONTAINERS Filed July 29, 1944Patented Dec. 7, 194a umrso s'rAres PATENT omc's 2.4mm mnon or s'rracmxomu. caosuaas I ro commune John owls, Baltimore, are, m a Continental CanCompany, Ine New York, N. Y., a

corporation of New York Application July so, 1m, Serial No. 54am 1Claim. (Cl. us-m) whether said body be of fiber or of metal so that theseam connecting the metal end to the body is of uniform tightness alongthe flat sides of the container and also along the rounded corners.

A further object of the invention is to provide a method of the abovetype, wherein the flange of the closure end at the rounded corners is sotreated before curling the same that said flange may be rolleddownwardly and inwardly into a smooth curl uniformly gripping the wallof a fiber container body.

A further object oi the invention is to provide a method of the abovetype wherein the flange or the closure end at the rounded corners is sotreated before seaming that said flange may be rolled with the flange ofthe metal can body into a tight double seam at the rounded corners aswell as along the flat sides of the container.

These and other objects will in part be obvious and will in partbe-hereinai'ter more-fully explained.

In the drawings,

Figure l is a plan view of a closure and after,

it has been formed with the fiange and the rounded corners of the flangenotched;

Figure 2 is a sectional view on the line 2-2 of Figure l; s

Figure 3 is a view showing more or less diagrammatically and in sectionthe initial step in the method of attaching a metal end to a fiberFigure 4 is a view showing the flange curled into gripping engagementwith the fiber body, the

view being taken at the rounded corner and at one of the notches in theflange: Figure 5 is a view on an enlarged scale showing a portion of acontainer having the metal and secured to the fiber body;

Figure 6 is a view showing the initial step in 2 \r taken at the roundedcorner and through a slit formed in the flange of the metal end-closure.While'the improved method may be employed for the securing of a metalend to either a fiber body or to a metal body, it is especially adaptedfor the connecting of a metal end to a fiber body having fiat sides androunded comers. The

method will, therefore, be described in detail inconnectlon with theforming of a fiber container 10 body having metal ends secured thereto.

16 to provide a metal end having a bottom portion,

surrounded by a substantially vertical wall 2 from which projects afiange 3. The metal end as shown in Figure 1, has parallel sidewalls andparallel end walls and these side and end walls 20 are Joined by roundedcorners indicated at 4 in the drawings. The flange at each roundedcorner is cut so as to provide V-shaped notches 5.

Each rounded corner, as shown in Figure l, is provided with two V-shapednotches. These V- 2 shaped notches extend only part way across theflange, terminating at the points indicated at a The fiber can bodyindicated at 1 may be of any desired construction, but is preferablyformed by convolutely winding is iiber strip on a mandrel into a tubeand the tube is then cut into ,body lengths. The fiber body, however,may be spirally wound if desired.- The depression in the metal endclosure is dimensioned so that it fits snugly within the container bodywith the flange of the metal end resting on the end of the wall of thecontainer body. After the parts have been assembled as shown in Figure8,9. chuck 8 conforming in shape to the recess in the can end is placedin engagement with the end, and a seaming die I is brought intoengagement with the flange 3 for curling the same. This seaming die ismade up of sections which are moved radially and inward'y for thecurling of the flange. Sectional dies of this type are well known in theart and a detailed description thereof is not thought necessary.

The sections of the die. however, are so dimensioned that the curledsurface is substantially to continuous when the curl formed in theflange is completed. The inward movement of the sections of the curlingdie will roll the outer edge of the flange into a curl, indicated at l0,and will roll the flange downwardly and inwardly as 05 indicated at llso as to press this curled edge In against the outer wall of the flberbody. The pressureoi' the seaming die will cause this curled edge iii tobe embedded in the flber body as shown in Figure 4.

Various eii'orts have been made heretofore to curl the flange of a metalend having flat sides and roundedcorners so that said curled edge willsnugly grip the wall of a fiber body. It is, however, difilcult to rollthe flange at the rounded corners so that it will grip the body due tothe fact that the flange as it is curled inwardly and downwardly iscontinuously moving to a shorter radius and this results in a puckeringof .the inturned part of the flange so that it does not lie smoothly incontact with the body wall. Applicant, in his new method, hasconstructed the flange of the metal end at its rounded corners withnotches and thus takes out sufficient metal so that the metalpartsremaining can be curled into a smooth substantially continuous contactwith the body wall. These notches are so dimensioned and extend into theflange a sufficient extent so that when the flange is curled; the sideedges of the notches will be brought into contact and therefore theinner curled part Iii which is embedded in the fiber body makes acontinuous line contact therewith.

These slots in the flnished curl do not interfere with the sealing ofthe end of the body wall as they terminate at the point indicated at iin Figure 4. The metal of the end directly above the end wall of thecontainer body is unbroken all the way around and therefore a very tightseal can be obtained. Likewise, a very tight grip can'be obtainedbetween the curled portion and the body wall which is likewisesubstantially continuous all the way around the container end. Thisproduces a seam wherein the metal is smoothly and uniformly rolled intogripping contact with the body. wall with a resulting tight ,seam whichflrmly joins the metal and to the flber body. In Figure'5 the end seamis indicated at I 2 and the contacting edges of the V-notches areindicated at ll, ll.

It will be noted from the above that the flange on the metal end is notprecurled but is dieshaped from its straight horizontal position shownin Figure 3 to the curled position shown in Figure 4 and the seamcompleted by one set of dies which are curved on their operating facesso as to conform to the curvature of the flange in its flnal form asshown in Figure 4.

As has already been noted. the improved method may be applied to thedouble seaming of a metal end to a metal body of a container having fiatsides and rounded corners. The container end.will be shaped the same asshown and described in connection with Figures 1 and 2. However, theflange will be of slightly greater width in order to provide suflicientmetal to form the interlocked hooks of a double seam. In Figure 6 of thedrawing there is shown a metal can body ['4 which is provided with aflange ll Joined to the body wall by a curved section It. The flange I!of the closure end ll overlies the flange it of the container body. Theclosure end has a recess surrounded .by a substantially vertical wall l9which carries the flange l1. After the parts have been assembled asshown in Figure 6, a chuck is inserted in the closure end and a seamingroll or a series of seaming rolls 2| are preferably used for the formingof the double seam. Either the seaming rolls or the can body with theclosure end clamped thereto are rotated. The seaming rolls as theytravel relative to the closure end being'seamed to the can body aregradually moved inwardly until the flange on the closure end is curledabout the flange on the body wall, as shown in Figure 6. The flange of gthe closure end is rolled downwardly and inwardly and this causes theflange on the container body likewise to be rolled downwardly andinwardly. In this figure there has been illustrated the flrst seamingoperation which is a loose loining of the closure end to the containerbody.

The container with the end thus attached is then submitted to a secondseaming operation. In this second seaming operation a chuck 22 isinserted in the end and a second seaming operation roll I! is caused toengage the partially formed seam and roll the parts into a tightlyinterlocked double seam. as shown in Figure 8. These seaming operationsare of the usual character and further detailed description thereof isnot thought necesary.

The flange of the closure end is provided with the V-shaped notches II.There are two notches at the rounded corners. This may be varied andmore than two used if desired. The notches are so dimensioned that whenthe flange is rolled into the double seam, the side edges of the notchesare brought into close contact. as indi cated at il in connection withthe seaming of a closure end to a flber body. The closed up notchextends to a point indicated at 24 in Figures 7 and 8. This does notinterfere with the seal as the metal parts are brought into intimatecontact throughout the upper portion of the double seam and the notchesare closed up so that the lower part of the double seam is substantiallyone continuous wall.

It has been found very difficult to roll the dense of a metal end into atight double seam at the rounded corners of a container having flatsides and ends {or the reason that the radius of curvature of thisrounded end is very small. The rolling of the flange downwardly andinwardly results in a shortening of the radius of the outer portion ofthe seam with the result that on this short radius of curvature of therounded end the metal will be gathered or puckered, which interfereswith the tightness of the seam. With these V-shaped notches. however.the flange may be rolled radially at all points inwardly into a verytight smooth uniformly curled double seam.

While it is preferred in the securing of the metal end to the metal bodyto use seaming rolls traveling about the end, it will be understood fromcertain aspects of the invention that a sectional die such as describedabove in connection with the fiber container body, may be used forcurling the flange of the metal end into a relatively tight seam withthe flange of the metal can body. Such a seam may be sufliciently tightfor many purposes, but when it is desired that a very tight seam shallbe produced, then it is preferred to use the seaming rolls.

the appended claim.

- corners of the container body. and a flange extending outwardly allthe way around the closure end. which flange overlies the body wall when1 notches in contact.

the flange at the rounded comersare substantially parallel, placing saidmetal closure end on the container body and curling the flangedownwardly and inwardly into locking engagement with the body member toprovide a smooth substantially continuous portion with the side edges ofthe JOHN COYLE.

6 nsmancas CITED The following references are oi record the file of thisM:

UNITED sums PATENTS Number Name Date Somers July 20, 1888 Adams Dec. 26,1916 Robinson Sept. 8', 1921 Bentley Aug. 20, 1929 Cameron -4. Apr. 1,1930 I McLain et al. Aug. 1, 1939 Frederick June 11, 1940-

